Django：使用“Unique Together”保存并通过 inlineformset 删除对象会导致错误页面

Question

对不起，如果这是一个简单的修复，我的内联表单集有 2 个问题：

1. 保存无效对象（不满足唯一性要求）会引发错误页面，而不是在表单中显示错误。

   在保存无效对象时，有时我的错误会正确显示，但当我尝试保存有效对象时，我会收到一条错误消息，提示 members.department 为空。这就是为什么我把“例如在实例中”，但现在我遇到了保存无效对象时不显示错误的新问题。

2. 我在删除有效对象时遇到了同样的问题。该对象被删除，但我仍然得到一个错误页面......

我迷路了。

当我保存无效对象时：

The Membership could not be created because the data didn't validate.

删除有效对象时我得到：

[u'Select a valid choice. That choice is not one of the available choices.']

型号：

class Membership(models.Model):
    project = models.ForeignKey(Project)
    department = models.ForeignKey(Department)
    employee = models.ForeignKey(Employee)
    role = models.ManyToManyField(Role, blank=True, null=True)
    class Meta:
        unique_together = (("project", "employee",),)

VIEW.py

def employee_edit(request, employee_id):
    i = get_object_or_404(Employee, pk=employee_id)
    MembershipForm = make_membership_form(i)
    MembershipFormSet = inlineformset_factory(Employee, Membership, exclude='department', extra=1, form=MembershipForm)
    if request.method == "POST":
        f = MembershipFormSet(request.POST, instance=i)
        if f.is_valid():
            instances = f.save(commit=False)
            for instance in instances:
                instance.department = i.department
                instance.save()
            f.save_m2m()
            return render_to_response('dbtest/edit.html', {'item': i, 'formset': f, }, context_instance=RequestContext(request))
    else:
        f = MembershipFormSet(instance=i)
    return render_to_response('dbtet/edit.html', {'item': i, 'formset': f, }, context_instance=RequestContext(request))

def make_membership_form(i):
    class MembershipForm(forms.ModelForm):
        project = forms.ModelChoiceField(queryset=Project.objects.filter(department=i.department))
        class Meta:
            model = Membership
            exclude = ('department', 'employee')
            unique_together = (("project", "employee",),)
    return MembershipForm

Answer 1

第一个错误消息非常简单。

The Membership could not be created because the data didn't validate.

您在保存表单集之前没有先检查它是否有效。如果 formset.is_valid() 为真，您应该只调用 save 。再看看my answer to your previous question